site survey and maping tools

[lanebob]

Howdy,

I have been working on mapping out my coverage areas. I have not found a very good system, and was wondering what other people are using. Presently, I am using topographical maps of my area, and going out and taking readings with my laptop for the pattern. Then when a potential customer calls, I can at least give a possible yes, or a definite no. It is far from slick. I am guessing that there are some other ways of doing things that could make my life better. I do have a small GPS device, but haven't yet rigged up the serial connection. Until I have a plan for what to use it for, I don't want to spend money uselessly. If I knew of a product that would work well, I could justify it tho.

Also, I would be interested in finding out if there are some generally excepted flow chart type diagram systems for showing my tower layout. It would be easier to get plans enacted if I was used to how things looked on a representative map with symbolic data at a glance. I would appreciate suggestions. Also, perhaps it would be easier for someone else to look at my layout if there were some conventions to follow. Perhaps even software I haven't yet heard of to do the drawing?

-lanebob

[Bossman]

We started out like you are now with topo maps, a ruler and calculators. Very time consuming but always accurate for us. Now we use the local SCADA company for the path studies. they already have the software, so we just send them the co-ordinates. Keep in mind that the elevation readings on GPS are not that accurate. I'm not sure if they have allowd more accuracy, but in the past it would usually fluctuate at least 200 - 300 feet (military reasoning).

We only do path studies for our backbone links and in planning expansions.

For all of our customer links I first guestimate thier position on my MS mappoint software and then usually can tell witin reason what the odds are. After a while you get to know the lay of the land and for many customers can just say yes. From there they read the contract and if they agree in principle we roll out and do a test shot so we have real world results.

Arthur

[dkii]

I found a great program called Radio Mobile Deluxe, http://www.cplus.org/rmw/english1.html It will take topo data from a variety of sources, including the most recent SRTM(shuttle radar topography mission, which is amazing resolution), all available to download free of charge, check the links on his site. It will overlay a map from mapblast with the proper scale, and you can place each of your units on the map and check line-of-site including terrain obstructions, etc.. It really is a great program, but it is a little tricky to learn to use, I've been playing with it for about 3 months and just getting to use its real abilities. It beats the crap out of running around with a gps and a pad of paper. After you download it and play with it a bit I would be glad to explain the really useful features of it.

[georgew]

Radio Mobile will do hours of math in a couple of mouse clicks.

Radio mobile combines USGS topo maps and mapblast street maps, and allows you to build your network and test it before you get your hands dirty. Of course it is all theory, but radio theory is a solid predictable thing, so except for not being able to predict ground clutter, it does a swell job. To predict ground cover I use mapquest.com aerial photos and estimate the tree lines, then I subtract the tree heights from the tower heights, so in effect I raise the ground to treetop level for radio predictions. It will plot line of sight regions, so you can tell beforehand which neighborhoods qualify for service. It will also predict radio signal coverage for NLOS predictions.

It also has a file called cities.dat that you can stuff your own map points into. I put up a tower, then drive around with a netstumbler rig. I then edit the netstumbler data and insert it into the cities.dat file to produce actual measured coverage plots, as well as plotting sources of noise. U use a number to indicate the channel, and a color to indicate signal level.

It has a feature to show a profile of a link, showing you where you are loosing clearence, so you can play with the antenna height, to help in planning the network.

You use a spreadsheet to predict the cash-flow of a future business plan... you use radio mobile for the same purpose. You can build and test your theory before begining construction.

Radio Mobile is used by professional broadcasters and is constantly evolving and improving.


It is a MUST have! And the price is right, the program and the data it depends on are all free. The catch is the topo data outside of the US and canada is based on 1000 meter resolution, which is NOT good enough for planning marginal LOS shots... so you want to get the best data possible before getting started. I've been itching for better topo data, as the USGS data is not real accurate. I would pay for better data, if I could find some that isn't $900 per square mile... The space shuttle mapping project is starting to produce data you can use, but I'm finding that data to be a bit "noisy" as it has not been cleaned up yet... but it has good 30 to 100 meter resolution for the most part. I would prefer 1 meter resolution that was as accurate as the mapblast maps, but you can't always have everything.


George

[dkii]

Ahh.. Noise... that explains the 45° herringbone type pattern I have been seeing in the srtm maps. I was trying to figure out where that was coming from. Do you think they will eventually get it smoothed out?

[georgew]

That is a good question. They have cleaned up the worst problems from what I gather, but it wouldn't suprise me if you have to buy commercial data to get anything better.


George